Author Topic: Front brake rebuild and upgrades, squeals worse than ever  (Read 2622 times)

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Offline RAFster122s

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #25 on: January 10, 2023, 01:17:53 AM »
Glad you are recovered from CoVID and some success with the brakes
David- back in the desert SW!

Offline Dunk

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #26 on: March 22, 2023, 07:10:02 PM »
Still squeals worse than ever. I have taken to hitting the disc by hand with 40 grit every day or two, sneak 120 grit on the pads occasionally. Silent right after that, for somewhwere between 16 and 32 miles... My typical commute is 16 miles each way either stop and go if I take back roads or highway if it's not rush hour. Disc and pads seem glazed within 15-30 miles, faster if I brake hard.

I got a fancy ghetto disc reconditioner. Did the outside tonight and it doesn't squeal at moving the bike in the garage speeds only doing one side. The sturggle is real, the squeal is super loud. I think the brake was a lot quieter without these fixed anti squeal pads. I'd think the pads have worn in by now but it seems like the disc and pads just glaze very quick no matter what I do. I use ear plugs, still super loud through my plugs but I feel bad for the other people on the road every day even if most try to kill me.

Online grcamna2

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #27 on: March 22, 2023, 07:37:07 PM »
I think another pair of pads is what my choice would be.
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Offline RAFster122s

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #28 on: March 22, 2023, 09:24:57 PM »
What brand of pads and what compound/composition are the pads?
Might be time for a different disc if a new set of reputable pads continues this problem. Trudisk can resurface the disk grinding it flat and parallel.
You mentioned having "roached or roasted the disc earlier. I would be surprised if it changed the stainless steel disk temper more than at a surface level.

Have you checked the disc for runout and seen if it is true?
David- back in the desert SW!

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #29 on: March 22, 2023, 09:39:30 PM »
What brand of pads and what compound/composition are the pads?
Might be time for a different disc if a new set of reputable pads continues this problem. Trudisk can resurface the disk grinding it flat and parallel.
You mentioned having "roached or roasted the disc earlier. I would be surprised if it changed the stainless steel disk temper more than at a surface level.

Have you checked the disc for runout and seen if it is true?

+1 on truedisk,LLC
I sent my OEM Honda disc out to him;he's a very precision person:he tests all the discs that come in for warpage.
He called me and told me my disc had a .006" bend in it;he straightened it before he machined it and it works excellent.  ;)
« Last Edit: March 23, 2023, 03:56:47 PM by grcamna2 »
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Offline Tracksnblades1

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #30 on: March 23, 2023, 01:38:34 PM »
Still squeals worse than ever. I have taken to hitting the disc by hand with 40 grit every day or two, sneak 120 grit on the pads occasionally. Silent right after that, for somewhwere between 16 and 32 miles... My typical commute is 16 miles each way either stop and go if I take back roads or highway if it's not rush hour. Disc and pads seem glazed within 15-30 miles, faster if I brake hard.

I got a fancy ghetto disc reconditioner. Did the outside tonight and it doesn't squeal at moving the bike in the garage speeds only doing one side. The sturggle is real, the squeal is super loud. I think the brake was a lot quieter without these fixed anti squeal pads. I'd think the pads have worn in by now but it seems like the disc and pads just glaze very quick no matter what I do. I use ear plugs, still super loud through my plugs but I feel bad for the other people on the road every day even if most try to kill me.

Dunk,

Is your front rotor hot at the end of your 16 mile journey.

I had the same problem on a 76F1. It turned out to be a tired caliper piston oring that just couldn’t back off the piston enough. It even squealed while pushing it by hand if the fork were turned one way but not the other way. Made it a witch to backup in parking lots…
Age Quod Agis

Offline Dunk

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #31 on: March 23, 2023, 03:21:59 PM »
Brake is not dragging, new oring recently and super clean inside. Brake squeals moving the bike around the garage and lightly touching the brake, same with light brake while riding.

The rotor did get very hot and discolored. I took it off and line sanded it with I think 80 grit while rotating it. Looked normal after that. Rotor is not hot, nor is caliper, at least the few times I've felt them. Warm yes, but not hot.

Brake pads I used are FB-45 out of the white box. I chamferred the edge of each pad all the way around before installing. Installed with grease around the OD of the metal backing. Antiqueal inserts between each pad and the caliper.

Rotor after ~32 miles, and after scuffing it with the new rotor surface tool.
« Last Edit: March 23, 2023, 03:23:46 PM by Dunk »

Offline Tracksnblades1

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #32 on: March 23, 2023, 03:40:47 PM »
Does your new oring provide the required clearance?
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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #33 on: March 23, 2023, 03:58:57 PM »
Dunk,do you have a spare disc to install to test if it works better than the one you have ?
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Offline Dunk

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #34 on: March 23, 2023, 06:37:02 PM »
Yes. This is an aftermarket disc from 4into1.I still have the original disc, which I've considered scuffing up and reinstalling.

Offline HondaMan

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #35 on: March 23, 2023, 07:37:41 PM »
I've had several things cause the symptoms you're fighting with. I'll just list them here (some of it was also in my book) and maybe you'll see something that might fit your situation?
1. Slightly corroded, poorly-recovering (after application) plunger valve in the master cylinder. It made every kind of pad squeal after a couple of miles, putting glazes on them with a slight drag after the first 2 or 3 stops. This usually showed up after the bikes were parked a long time.
2. Beveled the outer circumference of the new pad (yours looks like it already is: some are not), then cut an "X" across the face of the pads (both sides) with a hacksaw blade to prevent chatter & squeak. This was common with the 1974-76 Honda pads, and went away when we could get sintered (with brass bits) pads again around 1984 or so. The new calipers in the 1976-78 bikes used different (smaller) pads that were made of the same stuff as the K0-K4 pads, no squeal but an occasional squeak. These were all asbestos pads, though. I have never found that extra looseness (vertical wiggle/travel) of the caliper's arm made any difference, except once when it was so worn on a high-mileage K1 that it made a loud "clunk" each time the brake was applied after replacing the worn-out pads (80k miles). On that one I just replaced the O-rings on the pivot pin with thicker ones, which cushioned the arm's upward travel at each application: Honda recommended just replacing the hanger and arm. We didn't have one at the time.
3. In the 1990s, EBC came out with the "ecologically friendly" pads. These came in 2 types: ones that squeaked 100% of the time and those that don't squeak: they also don't stop very well, and in the wet, not at ALL. Avoid those if possible.
4. The clearance between the stationary pad and the disc should be 0.003"-0.006", as set with the adjuster screw and feeler gage between the pad and disc. If there is any air in the brake line, this clearance will also cause the brake to not engage until the lever is pulled nearly to the grip, so it is a good way to "test the bleed job" for completeness. I bleed by pulling the lever in until both of the little holes in the fluid reservoir show no piston in view, then wire it right there, open the caliper's bleed valve with the handlebars turned fully left, and leave it there for at least 1-2 hours (or overnight if not flowing). Then I'll wiggle the lever a couple of times (in that same handlebar position) to see if any bubbles appear, repeat until clear. Even one tiny bubble in the line will make the fluid expand and press the caliper gently against the brake, making it glaze, drag and squeak when warmed up.
5. [This is for rebuilt master cylinders] Make sure the new master cylinder piston is the same type as came out of the brake. There are 4 different types, and 3 different lengths, varying by about 2mm longest to shortest. The first type is found in the K0-K3 and early K4 built before [about] 1/1974, the second type is found in the later K4 thru the K6 and the earliest F0 bikes. Then it changed to the type found in the K7/8. The ones in the F2/3 are also different from the K bikes. What can cause trouble here is: using the later K4-K6/F0 type in the early bikes' master cylinder or vice versa: using the later ones in the early master cylinder will cause it to have no brake until you pull the lever a few times - and this happens every morning. The opposite is: the brake will not prime, period. The spring-relief valve is different in the 2 K master cylinder's valves, which causes the problem. "Generic" rebuild kits don't, in my experience, release the brake caliper very well - which sorta sounds like yours? It should release the caliper almost instantaneously with the brake lever release, if correct.

This last one has caused some "cafe" builders to use some other bike's master cylinder when their careless non-attention to these details caused them troubles and they didn't want to be bothered to fix it properly. ;)
« Last Edit: May 21, 2023, 03:20:10 PM by HondaMan »
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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #36 on: March 23, 2023, 08:46:13 PM »
I appreciate this information from HondaMan about the master cylinder;it seems that he's saying that it's better for the stock master cylinder to stay with the same model/year for best performance?
I was thinking about the tiny little bleed hole in the master;I wouldn't want to block access to that w/ the wrong size piston,it'll hold pressure in the caliper..
I'm curious if using a generic China master cylinder is acceptable ?
« Last Edit: March 24, 2023, 05:41:41 PM by grcamna2 »
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Offline dave500

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #37 on: March 24, 2023, 01:19:17 AM »
i have a cast iron disc on my 500,so much better friction coefficient plus a 12.5mm bore cheapie master and its pretty good,no squeal,good feel and half the effort to stop with no fade in fact it gets better when taxed on a downhill run and is actually less weight slightly!,#$%* the stainless was never a good brake material from the get go but looks good.

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #38 on: March 24, 2023, 10:38:55 AM »
i have a cast iron disc on my 500,so much better friction coefficient plus a 12.5mm bore cheapie master and its pretty good,no squeal,good feel and half the effort to stop with no fade in fact it gets better when taxed on a downhill run and is actually less weight slightly!,#$%* the stainless was never a good brake material from the get go but looks good.

I love cast iron,when I can find it for vintage bikes.
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
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Do your BEST...nobody can take that away from you.

Offline evinrude7

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #39 on: March 24, 2023, 03:35:32 PM »
I took a small piece of 2x4 and wrapped a sheet of sandpaper around it. Block sanded my disk last time it was off for spokes. One section at a time, rotating the disk to a new area after what seemed like enough sanding.  Think I used 100 grit. Not sure if that's what did it but hasn't been noisy since.

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Offline Dunk

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #40 on: May 21, 2023, 02:45:35 PM »
My latest attempt, I slotted the existing pads vertically as many new pads are. Hondaman's thoughts along with changing pads on my XL600 with slotted/grooved pads got me thinking about it. If the vertical slot doesn't help I may try an X as Hondaman suggests.

The master cylinder variances are interesting. This master has been rebuild using all parts from an aftermarket kit, no idea what the master came from or what else may have been changed as I've only had this bike since 9/2015. Maybe it is not releasing quickly or releasing enough, glazing after every couple hundred miles.

I also have the adjuster screw/spring setup removed as others have suggested. It seemed to help some in that it would take longer before squeal set in bad, maybe a symptom of the master cylinder issues.

Dave has me considering a cast disc, so it can be all rusty and crusty since I live in the rainy mid-atlantic. https://www.ebay.com/itm/275354820239

Offline HondaMan

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #41 on: May 21, 2023, 03:29:17 PM »
Those pads in your picture look like the ones I fought that came from EBC. They have no visible sintering (brass) bits in them, which is the material used to prevent the squeak, and they are that same light color.

I haven't bought new brake pads in quite a while. I think the last time I went thru it all (again) was in 2010 when I rebuilt a 750F0 for a friend of mine. Happily the rear pads were OK, but the front ones had been replaced with the die-in-the-rain pads from EBC, so i pulled them immediately and spent $$ several times to get some that didn't scream from being squeezed. The ones that finally worked right were a medium-dark color, not black nor tan, and had the sintering bits spread heavily throughout the material. They weren't from EBC, but at the moment I can't remember where they did come from.
 :-[
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Offline Dunk

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #42 on: May 21, 2023, 04:29:22 PM »
I suspect these are EBC. There is some sintering in them but I wouldn't know how much is a little or a lot. They were darker on the face when glazed over, lightened up substantially when i roughed up with 40 grit. I have two other brands of pads to try after these. Not sure what makes a "good" or "bad" pad.

Online grcamna2

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #43 on: May 21, 2023, 04:50:22 PM »
I like the cast iron rotor;I'm sure it'll be a Win-Win for you.
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  I love the small ones too !
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Offline dave500

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #44 on: May 21, 2023, 11:38:11 PM »
with a cast iron rotor before you fit it you could clean and paint the edge and inside the vent holes?a cotton bud would work in the holes?

Offline willbird

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #45 on: May 22, 2023, 06:18:31 AM »
it would be cool if we could get TBM to make us some brake disks :-).

https://www.tbmbrakes.com/products/3-10753105525d

Wonder if anything they make is the right size ?? They are designed to be able to get cherry red temperature and still be flat when they cool down.

Offline Dunk

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #46 on: July 16, 2023, 10:38:28 AM »
I finally got the cast iron rotor installed. I used rattlecan caliper clear on the whole thing. Since my pads are probably trash I used them to wear through the clear. Most of it is gone in a short test ride. Brake is quiet and works well. After seeing most of the clear gone I removed the pads and hit them with fine and then course sandpaper. So far quiet and good stopping power. Hopefully it stays quiet.

The stainless rotor from 4into1, super loud, weighs 4 lbs 12 oz. The cast iron rotor from Australia weighs 4 lbs 11 oz. I used the round head studs and nylocks that were on the 4into1 rotor. Instructions suggest using botton head M6 x 16mm screws with nylocks through bolted, or use a M6 heliciol in the hub and use M6 x 12mm botton head screws attached to the hub. Fit was tight from disc ID to hub OD, slight press fit tapped it down partway with a dead blow and pulled it the last bit tight with the bolts.

Online grcamna2

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #47 on: July 16, 2023, 12:54:16 PM »
Fresh pads to go with your fresh cast iron rotor ?  :D
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  I love the small ones too !
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Offline Dunk

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #48 on: July 16, 2023, 05:01:57 PM »
Yes I have two new sets of pads, one ceramic the other not. Unsure which to use. I want to be sure I've worn through the entire clear coat to not contaminate the new pads. Probably be good to swap fresh pads after one ride to work on the back roads stop and go. Compromise between not having a ball of rust for a rotor since I ride this bike regularly in the rain, and coating but just wearing through the clear coat. Couldn't figure a reasonably easy way to mask off just the friction surface, and it started rusting within a minute after I cleaned off the oil wiped on it for shipping.

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Re: Front brake rebuild and upgrades, squeals worse than ever
« Reply #49 on: July 16, 2023, 06:28:16 PM »
Yes I have two new sets of pads, one ceramic the other not. Unsure which to use. I want to be sure I've worn through the entire clear coat to not contaminate the new pads. Probably be good to swap fresh pads after one ride to work on the back roads stop and go. Compromise between not having a ball of rust for a rotor since I ride this bike regularly in the rain, and coating but just wearing through the clear coat. Couldn't figure a reasonably easy way to mask off just the friction surface, and it started rusting within a minute after I cleaned off the oil wiped on it for shipping.

You may find something to(sanding block with Medium grit emery?)remove all clear coat residue on both friction surfaces before installing non-ceramic pads.
I hate to see you still struggle with squealing because of that residue. Cast iron rotors rust,but you use your bike often so it won't be an issue for stopping;the riders with cast iron rotors are use to the rusty look and most love how they stop and are willing to have a little surface rust.
75' CB400F/'bunch o' parts' & 81' CB125S modded to a 'CB200S'
  I love the small ones too !
Do your BEST...nobody can take that away from you.